<!DOCTYPE html>
<html class="reftest-wait">
<head>
  <style>
    .flexContainer {
      display: flex;

      width: 300px;
      height: 300px;
      background: yellow;
    }
    .flexItem {
      border: 1px dashed purple;
    }
  </style>
  <script>
    function finish() {
      document.documentElement.removeAttribute('class');
    }
  </script>
</head>
<body onload="setTimeout(finish, 0)">
  <div class="flexContainer">
    <embed src="about:blank" class="flexItem"></embed>
  </div>
</body>
</html>
